A portable photographing device for photographing an image includes a digital camera, a digital video camera and the like. A device for projecting an image onto a wall surface or a screen includes a so-called projector. As the projector, a device of a so-called stationary type is a mainstream, in which a power is supplied from a commercial power supply thereto and the device is used in a fixing state into a predetermined position. The projector of the stationary alone type projects an image onto a wall surface or a screen in a certain place in the fixing state. On the other hand, in recent years, a portable projector which is small-sized and is easy to carry is proposed as the projector.
Patent Literature 1 describes a portable electronic apparatus having an image capturing function and a projector function, including an photographing device for picking up a subject image and outputting an image signal, a projector device for projecting an image formed on a light image forming element, image change detecting means for detecting a change in the image signal, indicating means for giving an instruction related to an operation of the projector device corresponding to a region in which the change in the image signal is detected, a display device capable of displaying an image obtained by pickup of the photographing device, and display control means for controlling a display content to be displayed on the display device and causing the display device to carry out a display corresponding to the instruction.
Furthermore, Patent Literature 2 describes a portable terminal device for projecting an image onto a touch panel or a key button by means of a projector. The portable terminal device described in the Patent Literature 2 projects a character, a numeral, a mark or the like which is allocated to each portion of the touch panel in the case of an input mode.